May give it a shot... I've never really played Tower Blitz but could give it a shot later today maybe?

It’s complete up to you, I think it’s a pretty good game though

Does it take time to grind for in-game currency to be able to solo win on the easiest difficulty ? like how many days if i play an hour every day

To get all the shop towers not including contract ones it will take maybe 3-5 hours, I suggest going on roundabout with sharpshooter on expert. Place a 2-4 sharpshooter and spam 4-0 sharpshooter till you die

Neat.